PSU buying advice - Focus PX 750 vs Prime PX 750 vs Prime TX 750

[DRDOOM]

I'm looking to upgrade my 550W PSU to a 750W in preparation for the RTX 3080. I've narrowed my search down to these three Seasonic PSUs, the Focus PX 750 vs the Prime PX 750 vs TX 750

Simply put, which one should I go for? Budget is not a concern. Any pros and cons to each of the power supplies?

 

[JustAnEngineer]

The Prime PX-750 has a larger fan than the Focus PX-750. Both of those have the same dimensions. The TX-750 is more efficient (80+ Ti vs. 80+ Pt).

 

[dirtyferret]

All three are excellent and come with at least ten year warranties so Seasonics believes they will last you a good amount of time. In the real world you won't notice a difference between them. Get the cheapest one and save your money for the RTX 3080.

 

[Bill_Bright]

I absolutely and totally agree it is essential to get a quality, efficient PSU. But I see no reason to waste money on Titanium certified PSUs. And unless they go on deep discounted sale, I see no reason for Platinum either. "Gold" certified is just fine.

Even if money is not an issue, that does not mean it makes sense to waste it. It would take years of heavy use for the couple points in better efficiency to result in energy cost savings that make up the initial costs of purchase for the higher rated PSUs - unless, as mentioned the merchant is offering deep discounted sales prices for the Platinum. Titanium is really just for bragging rights, IMO.

It is important to remember that higher 80 PLUS efficiency certifications do NOT indicate better quality power, or a better quality PSU. Those certs have nothing to do with regulation, ripple suppression, hold-up times, voltage tolerances, or build quality.

Yes, a larger fan is nice, but 120mm is by no means tiny - or a con. And for sure, it is still a quality fan that no doubt will be extremely quiet to near silent the vast majority of the time. In a quality case, when your system and that graphics card are being taxed, I am sure if you hear any fan noise, it will be from the graphics card and/or case fans and not the PSU.

And while Seasonic is certainly a top brand to consider, they aren't the only quality PSU maker.

If you are locked on only those three, I agree with DF - get the cheapest and put the money you save elsewhere - like more RAM, nicer monitor, or a gift for your better half. If you don't have one, then a gift for your mom.

 

[Ruru]

My vote goes for Seasonic as well. I've had the older FX-series Focus+ Gold 750W for over an year and I have nothing to complain. I had a R9 290 CF before and worked totally without any problems. Also the 10 year warranty is a good thing to have.

 

[xtreemchaos]

TX-750 more efficient but there all darn fine PSUs.

 

[Selaya]

[ ... ]
Even if money is not an issue, that does not mean it makes sense to waste it. It would take years of heavy use for the couple points in better efficiency to result in energy cost savings that make up the initial costs of purchase for the higher rated PSUs - unless, as mentioned the merchant is offering deep discounted sales prices for the Platinum. Titanium is really just for bragging rights, IMO.

[ ... ]

(Correct me if I'm wrong, I guess?) Thermals. An uptick in efficiency from 90% to 95% should half the amount of (waste) heat a PSU generates; in fact the Prime TX is so efficient Seasonic's offering a fanless version of it up to, uh I believe 600W? That is the main reason to buy a Titanium rated PSU (besides the aforementioned bragging rights ), imho. (ie, if you're running a thermally constrained build like, something fully passively cooled, or something.)

 

[P4-630]

You might want to go with a higher wattage PSU for future upgrades.

 

[JustAnEngineer]

Above 750 watts, the Prime PSUs are deeper than equivalent Focus units.

 

[juular]

If budget if not of concern then Prime TX, it's barely better than Prime PX but better nonetheless. If you rather want cheap but still very good option i'm pretty sure there should be other PSUs other than from Seasonic as Seasonic Focus isn't usually one of the best options neither value nor performance wise.

 

[Bill_Bright]

(Correct me if I'm wrong, I guess?) Thermals. An uptick in efficiency from 90% to 95% should half the amount of (waste) heat a PSU generates;

Ummm, no. That would be almost logarithmic. Its not. Its linear.

How could it be 50% less heat with only 5% increase in efficiency? My calculous is a bit rusty but if your statement were true, you would be talking steel melting temperatures compared to your basic, generic 70% efficient PSU.

Remember, it is very rare for a properly sized PSU to be maxed out. This is because a properly sized PSU must assume the CPU, GPU, motherboard, all drives, all fans, and everything else the PSU is powering are all demanding maximum power at the exact same point in time. And the odds of that are slim at best and even if it occurs, it will only be for a second or two at a time.

I don't know where you are getting 5%.

Gold is 87% at 20% load. 90% at 50% load. 87% at 100% load.
Titanium is 92% at 20% load. 94% at 50% load. 90% at 100% load.

But lets use your 5% and assume 50% load on that 750W supply.

50% load on a 750W supply = 375 watts.

At 90% efficiency, that means the PSU must pull from the wall 417W (417 x .9 = 375.3).
At 95% efficiency, that means the PSU must pull from the wall 395W (395 x .95 = 375.25).

As you can see that 5% better efficiency means just 22W difference - 22W in the form of heat. Hardly 50%, right? And a 22W space heater sure wouldn't do much to keep closet warm on a cool day. Depending on the fuel and who you talk to, the heat from on candle is 40 to 70W! So even if the demand on that PSU was its full 750W capacity, you are still only talking 44W difference - actually less than that since the 80PLUS cert says 3% difference between Gold and Titanium at 100% load.

It would take a very long time for 22W to consume 1kWh (kilowatt hour) of energy. Remember, 1kWh is how much energy an appliance consuming 1000 watts continuously uses in 1 hour. The typical home computer is turned off or in standby mode most of each day. And when it use, most are consuming closer to their idle consumption rates than maximum consumption rates most of the time.

And the average cost per kWh hour in the US is about $0.14.

So my point stands. It would take years to make up the difference in costs between Gold and Titanium - unless you managed to score a fantastic deal.

in fact the Prime TX is so efficient Seasonic's offering a fanless version of it up to, uh I believe 600W?

But it is not just about efficiency. It is very much also dependent on the MASSIVE heatsinks inside, HUGE vents in the PSU housing, and taking advantage of the Law of Physics that says heat rises - as is up and out of the supply.

 

[jboydgolfer]

ive been buying the Focus+ Golds for a handful of years now, theyre really nice, without requiring the silly prices like the platinum PSU's have.
im all for investing in a good power supply, but i refuse to spend extra for the super duper ultra silent unobtanium edition PSU's. Gold will suffice, & always has for me.

$85 for the Focus+ gold 750 was what i last paid

EDIT*
holy hell! is that what Seasonic PSU's are going for now?! $160+ Glad i bought when they were half that

 

[DRDOOM]

If budget if not of concern then Prime TX, it's barely better than Prime PX but better nonetheless. If you rather want cheap but still very good option i'm pretty sure there should be other PSUs other than from Seasonic as Seasonic Focus isn't usually one of the best options neither value nor performance wise.

One of the reasons why I considered the Focus because it was rated the best 750W PSU to buy by Tom's Hardware

Best Power Supplies 2024

These PSUs offer the best reliability, performance and protection for your system and its components.

www.tomshardware.com

The Prime PSUs appear to receive universal praise however. So I presume from Seasonic, those would be the ones to go for? What other options do I have in the 750W range?

In terms of costs, the Prime TX is £199, Prime Px £179, and Focus PX £123.

 

[Elisis]

I've narrowed my search down to these three Seasonic PSUs, the Focus PX 750 vs the Prime PX 750 vs TX 750

Are you willing to buy any PSUs other than these three? Because (depending on the country) it's likely that none of these will be worth it to you.

 

[DRDOOM]

Are you willing to buy any PSUs other than these three? Because (depending on the country) it's likely that none of these will be worth it to you.

How so? What would you recommend instead?

 

[Bill_Bright]

Not sure how the country would determine the "worth" but for sure, not all supplies are available in all markets. And also, some supplies cost more in different markets too. Perhaps that's what Elisis meant.

 

[Elisis]

Not sure how the country would determine the "worth" but for sure, not all supplies are available in all markets. And also, some supplies cost more in different markets too. Perhaps that's what Elisis meant.

I was more going for the angle of there being better PSUs for the price depending on the market.

 

[DRDOOM]

I was more going for the angle of there being better PSUs for the price depending on the market.

I'm from the UK. Which PSUs are better for the price?

Reading Amazon/Newegg reviews for some of the cheaper PSUs scare the hell out of me, particularly as some have reported their new PSUs destroying their existing components (eg motherboard, hard drive) upon insertion!

I do not mind paying more for absolute quality.

 

[JustAnEngineer]

Ummm, no.
How could it be 50% less heat with only 5% increase in efficiency? My calculus is a bit rusty but if your statement were true, you would be talking steel melting temperatures compared to your basic, generic 70% efficient PSU.

It's just multiplication, division, addition and subtraction in this case.

If PSU A is 94% efficient between 20% and 90% of maximum capacity, and PSU B is 94% efficient in that range and PSU C is 75% efficient, we can calculate their inefficiencies pretty easily.

PSU A, providing 600 watts of power inside your PC to your very hungry graphics card(s) and CPU is pulling 600 watts ÷ 0.94 = 638.3 watts from the wall. Its inefficiency (the amount of input power being turned into heat) is 638.3 - 600 = 38.3 watts. We can also get that number by multiplying 600 watts x (1.00-0.94)÷0.94
PSU B has 66.7 watts of inefficiency.
PSU C has 200 watts of inefficiency.
That's a pretty significant difference, even if it is less than your high-end Comet Lake and Ampere are using.

 

[Caring1]

I'm from the UK. Which PSUs are better for the price?

Reading Amazon/Newegg reviews for some of the cheaper PSUs scare the hell out of me, particularly as some have reported their new PSUs destroying their existing components (eg motherboard, hard drive) upon insertion!

I do not mind paying more for absolute quality.

As long as it is a known name brand and gold rated it should be fine.
Generally there are more people writing reviews that have a complaint, happy campers just get on with life.

 

[DRDOOM]

Based on reviews it appears there is very little to set apart the Prime series PSUs, besides the efficiency improvements.

I've found the Prime GX 750 for £150 (£50 cheaper than the TX 750), so I think I might bite the bullet and order.

Good for Gold, or just go for the Titanium?

 

[Selaya]

Ummm, no. That would be almost logarithmic. Its not. Its linear.

How could it be 50% less heat with only 5% increase in efficiency? My calculous is a bit rusty but if your statement were true, you would be talking steel melting temperatures compared to your basic, generic 70% efficient PSU.

Remember, it is very rare for a properly sized PSU to be maxed out. This is because a properly sized PSU must assume the CPU, GPU, motherboard, all drives, all fans, and everything else the PSU is powering are all demanding maximum power at the exact same point in time. And the odds of that are slim at best and even if it occurs, it will only be for a second or two at a time.

I don't know where you are getting 5%.

Gold is 87% at 20% load. 90% at 50% load. 87% at 100% load.
Titanium is 92% at 20% load. 94% at 50% load. 90% at 100% load.

But lets use your 5% and assume 50% load on that 750W supply.

50% load on a 750W supply = 375 watts.

At 90% efficiency, that means the PSU must pull from the wall 417W (417 x .9 = 375.3).
At 95% efficiency, that means the PSU must pull from the wall 395W (395 x .95 = 375.25).

As you can see that 5% better efficiency means just 22W difference - 22W in the form of heat. Hardly 50%, right? And a 22W space heater sure wouldn't do much to keep closet warm on a cool day. Depending on the fuel and who you talk to, the heat from on candle is 40 to 70W! So even if the demand on that PSU was its full 750W capacity, you are still only talking 44W difference - actually less than that since the 80PLUS cert says 3% difference between Gold and Titanium at 100% load.

[ ... ]

Example numbers. However, the delta between 417-375=42 and 395-375=20 is basically 100%, or double/half - ie, the 90% efficient PSU generates 42W of heat, while the 95% generates 20W - that making sense yet?

[ ... ]

It would take a very long time for 22W to consume 1kWh (kilowatt hour) of energy. Remember, 1kWh is how much energy an appliance consuming 1000 watts continuously uses in 1 hour. The typical home computer is turned off or in standby mode most of each day. And when it use, most are consuming closer to their idle consumption rates than maximum consumption rates most of the time.

And the average cost per kWh hour in the US is about $0.14.

So my point stands. It would take years to make up the difference in costs between Gold and Titanium - unless you managed to score a fantastic deal.

But it is not just about efficiency. It is very much also dependent on the MASSIVE heatsinks inside, HUGE vents in the PSU housing, and taking advantage of the Law of Physics that says heat rises - as is up and out of the supply.

100% agreed. The power consumption shouldn't be the reason you'd be wanting a Titanium PSU assuming current price deltas between Gold, Platinum and TItanium.

 

[juular]

I'm from the UK. Which PSUs are better for the price?

Bitfenix Whisper M, Super Flower Leadex III, Corsair RM-x, Fractal Design ION+.

 

[Athlonite]

One of the reasons why I considered the Focus because it was rated the best 750W PSU to buy by Tom's Hardware

Best Power Supplies 2024

These PSUs offer the best reliability, performance and protection for your system and its components.

www.tomshardware.com

The Prime PSUs appear to receive universal praise however. So I presume from Seasonic, those would be the ones to go for? What other options do I have in the 750W range?

In terms of costs, the Prime TX is £199, Prime Px £179, and Focus PX £123.

Take the Focus PX as you like me use 240V if your in England the actual 80+ rating goes up a notch (well almost) vs those using 120V in the likes of the U.S.

 

[Elisis]

if your in England the actual 80+ rating goes up a notch

Why would you care about this? It's not as if efficiency matters to, well, any consumer.